Duloxetine

Return to Duloxetine overview

You can drink some alcohol while taking duloxetine

If you drink alcohol, you can continue to drink some alcohol while taking duloxetine.
Drinking alcohol every day, however, can make the symptoms of depression worse and you will not feel the benefit of your medicine.
Side-effects might make you sleepy or you might lose your focus when you first start taking duloxetine.
This could be dangerous if you drive or use machines or do anything that needs a lot of focus.
So, during the first few days, it might be best to stop drinking alcohol until you see how the medicine affects you, or until the effects pass.

Do not drive or ride a bike just after you start taking duloxetine

Taking duloxetine may affect your concentration to do things like driving a car, riding a bike, using machines, or anything else that needs a lot of focus.
Your eyesight can be affected, and you can feel sleepy or dizzy.
It might be best to stop doing these things for the first few days, until you know how it affects you or until the effects pass.
You have to make sure that you are safe to drive.
You could go and practise emergency stops in a safe place, or get a friend or family member to go with you and see if they notice a difference in your driving.
Do not worry - most people drive as normal while taking duloxetine.

Try not to take duloxetine for the first time just before your exams

Taking duloxetine may affect your ability to do things that need a lot of focus, like exams.
Your eyesight may be affected, and you might have sleep problems or feel very sleepy during the day. You may also feel restless and find it hard to sit down and keep still.
You should talk to your doctor about any future exams if you are starting duloxetine.
You might decide together to delay starting it until you have done them. If they are more than a month away, however, you might find that it is better to start duloxetine to lift your mood and improve your motivation to study.
Do not worry - most people do exams as normal while taking duloxetine.

Duloxetine is not a banned substance in sport

Duloxetine is not a banned substance in sport.
Taking duloxetine may affect your ability to do things like riding a bike, competitive gymnastics, or anything else that needs a lot of focus. It can affect your eyesight, make you feel dizzy and sleepy, and make you feel restless and unable to sit still.
It might be best to stop such sports for the first few days, until you know how it affects you or the effects get better.
Do not worry - most people do sports as normal while taking duloxetine.

Your weight can be affected by duloxetine

A side-effect of duloxetine can be not feeling as hungry as normal, which might lead to weight loss.
Some children and young people aged under 18 who took duloxetine had some weight loss at first, but after 6 months of treatment they went back to normal compared with other people of the same age.
It is very difficult to know how it will affect each person who takes it.
Talk to your doctor about this if it worries you.

Duloxetine may make you sleepy, and may also cause sleep problems

You can feel sleepy in the first few days of taking duloxetine. It should, however, get better after the first week or two.
It can also give you sleep problems, including unusual dreams.
If you feel very sleepy or weary, and you’ve been taking it for more than a month, you should go back to the doctor and see what else you could do.

Let your family and friends know you are taking duloxetine so they can support you and help you look out for side effects

The side-effects of duloxetine might put a strain on your friendships and relationships, especially in the first few days of taking it.
You may become more anxious, for example, or it may make you irritable.
These side-effects should get better after a few days.
After a month you should be getting the good effects of duloxetine, and that should improve your relationships in itself.
It might actually be a great idea to choose a good friend to tell about your medicine when you start taking it. (Or - even better - to take one with you to the doctor before you start taking it!)
They could look at the medicine leaflet, or at this website.
They could then help you to understand whether the medicine changes your behaviour, or gives you side-effects (sometimes it is hard for us to see it ourselves).

Duloxetine can have side-effects that might affect your sex life

The good effects of duloxetine may, after a while, have a good effect on your sex life as your mood lifts and you become interested in life and relationships again.

There are, however, possible negative side effects that include:

Men might get problems with getting hard (getting an erection) and coming (ejaculating)
Women might have some unusual bleeding from their vagina
Men may get pain in their testicles (balls)
Women might not come (reach orgasm) the same way as before
You may have a lower sex drive
Both men and women might see some growth in their breasts, and some milk flow
If you lose weight, or get other physical side-effects, you may just not feel as sexy as before

These effects should pass after the first couple of weeks. If they do not, and this is a problem for you, go back to the doctor and see what else you could try.

Duloxetine does not seem to affect human fertility

In tests, duloxetine did not affect male fertility, and only affected female fertility at doses much higher than we would normally see.

You need good contraception when you are taking duloxetine. Talk to your doctor about your duloxetine if you are trying to get pregnant.

You should use good contraception when you are taking duloxetine. This is because we do not know the effects of duloxetine on a developing baby.
If you do become pregnant while you are on duloxetine, you should carry on taking the medicine and go back to your doctor as soon as possible, to see if you should change or stop your medicine.
Remember that you need to stay well through your pregnancy, and you may need a medicine to help you to do that.

Women who are planning a pregnancy should talk to their doctor about their options. They may agree not to take duloxetine, but it is important to stay well through the pregnancy.

Duloxetine can cause symptoms in newborn babies. Duloxetine is passed to the baby in breastmilk.

There are possible problems for the baby if you take duloxetine in the early stages of pregnancy.
If you agree - with your doctor - to carry on taking duloxetine, you should tell your midwife that you are taking it before you give birth.
If duloxetine is taken in the last 3 months of a pregnancy, it may cause a serious condition called persistent pulmonary hypertension of the newborn (PPHN).
This can make the baby breathe faster and look a bit blue in colour.
This happens in the first 24 hours after birth: you will need help from the midwife and doctors, so it is better if they are looking out for symptoms.
The newborn baby may also develop other side effects:
- Shaking
- Being floppy
- Being irritable and crying a lot
- Having difficulty sleeping or sucking
These might not happen straight away, so you should look out for them over the first few days after the baby is born.
A newborn baby may experience withdrawal symptoms after birth, which may include floppiness, shaking, jitteriness, difficulty feeding, breathing problems or fits (seizures).
Your midwife can help you to look out for these symptoms. They can happen immediately after birth or in the first few days of life, so ask for help to watch for these effects.
A small amount of duloxetine is passed to the baby in breastmilk, and side-effects have been seen in breastfed babies.
Talk to your doctor or midwife about your feeding options.

High doses of caffeine taken with duloxetine may bring on serotonin syndrome

If you drink a lot of coffee, cola drinks or caffeine drinks when taking duloxetine, it can put you at a higher risk of getting serotonin syndrome.
The symptoms are any combination of the following symptoms - high fever, agitation, confusion, trembling, sweating, diarrhoea (loose poo), fast heartbeat or weird movements of your muscles.
You need to go to a hospital straight away if you get these symptoms.
Large doses of caffeine can bring on or worsen generalised anxiety and panic attacks, or bring on mania, so it may also make the underlying problem worse.
For all these reasons, it may be a good idea to limit caffeine while taking duloxetine.

If you start or stop smoking while you are taking duloxetine, you may have to change your dose

Cigarette smoke affects the amount of duloxetine in your body.
If you smoke, you will probably need a higher dose of duloxetine than someone who does not smoke.
Tell your doctor if you smoke, so that you get the right dose for you.
If you stop smoking, the body duloxetine level rises and you might need to reduce your dose of duloxetine slowly.
If you (re)start smoking, you will probably need to increase it again.
Go to your doctor for advice if you stop or start smoking.
It is the smoke, rather than nicotine, that has this effect so it should not be as much of a problem if you only use an e-cigarette.

Reference sources

Theoretical enzymatic interaction reported in Cymbalta SPC 4.5 Updated 08-Feb-2017
https://www.medicines.org.uk/emc/medicine/15694 Accessed 21/02/2017

Cymbalta SPC 4.6 last updated 8 Feb 2017
https://www.medicines.org.uk/emc/medicine/15694 Accessed 21/02/2017

Cymbalta SPC 4.7 last updated 8 Feb 2017
https://www.medicines.org.uk/emc/medicine/15694 Accessed 21/02/2017

Cymbalta SPC 4.8 last updated 8 Feb 2017
https://www.medicines.org.uk/emc/medicine/15694 Accessed 21/02/2017

Not in WADA 2016 list

Cymbalta PIL 4 last updated January 2017
https://www.medicines.org.uk/emc/PIL.15601.latest.pdf Accessed 21/02/2017

Maudsley 12^th ed p692-3.
Theoretical interaction due to similarity between SNRIs and SSRIs. Caffeine releases noradrenaline.

Maudsley 12^th ed p688.